Lybrate Logo
Get the App
For Doctors
Last Updated: Oct 23, 2019

Pulmonary Function Tests - Why So Important?

Profile Image
Dr. Vivek PatilPulmonologist • 37 Years Exp.MBBS, Diploma in Tuberculosis and Chest Diseases (DTCD), AFIH
Topic Image

Lung function is a major indicator of health since it determines the amount of Oxygen that a body gets. Doctors resort to Pulmonary Function Tests if there is a problem with breathing or the lungs. Pulmonary tests give insight into how the lungs are functioning.

These tests measure parameters like lung capacity, lung volumes, gas exchange, rate of flow, etc.

Armed with information from these tests, the doctor can decide whether a person has some issues with the lungs or not, and accordingly diagnose and decide the line of treatment for accelerated recovery.

Type Of Pulmonary Function Tests

  • For all practical purposes, PFT can be divided into two broad categories: Basic and Advanced.
  • Basic PFT is Routine Spirometry but advanced PFT includes a plethora of tests.

Basic PFT: Spirometry-

  • This test measures how much air a person can inhale and exhale, as well as how fast one can empty the lungs.
  • In this test, a person needs to breathe into a tube. The tube is attached to a computerized Spirometer.
  • Before the test, nostrils will be closed with a clip. The person will also need to create a seal around the tube so that there is no leakage of air.
  • The patient will be asked to take a deep breath and then breathe out as hard as possible through the tube.
  • The doctor may ask the person to repeat the effort three times or more so that he gets a consistent result.
  • Estimating PEFR(peak expiratory flow rate) by Peakflometry and measurement of peripheral oxygen saturation(SpO2) by Pulse Oximetry can be included as a part of basic PFT for the purpose of completion.
  • These tests apart from giving valuable information are very simple to perform and patient-friendly which can be done by patients at home or at the doctor’s clinic on a regular basis.

Advanced PFT
Advanced Pulmonary Function Testing includes different tests like:

  • FeNO(fractional exhaled nitrous oxide),
  • DLCO or TLCO(diffusion capacity or transfer factor),
  • Body Plethysmography,
  • Impulse Oscillometry,
  • 6MWT (6-minute walk test), etc

Why Undergo Pulmonary Function Tests?

Doctors may conduct Pulmonary Function Tests even on healthy people. It is a mandatory part of pre-employment and peri-employment workups in most industrial and corporate health checkup programs. If a person works in certain hazardous environments like graphite factory, coal mine, chemical factory, etc., the employer may order such tests on a regular basis. People working in such places are at increased risk of developing respiratory problems which could be detected on PFT at an early stage.

PFT is an important investigation for evaluating common respiratory symptoms like:

It is a very crucial diagnostic tool for diagnosing chest diseases like:

  • Asthma,
  • COPD,
  • Other Airway disorders,
  • Interstitial lung diseases,
  • Occupational lung diseases,
  • Pulmonary fibrosis,
  • Connective tissue diseases related to lung involvement, etc.

In a Nutshell-

  • PFT is a set of tests which act as a window to lungs functioning of an individual.
  • One of the Pulmonary Function Tests may be advised by a doctor for a variety of reasons.
  • These tests are a way to measure the parameters of working/functioning of the Lungs so that a Physician can treat the problem effectively (if detected) and then follow up to assess the effectiveness of treatment or progression of the disease process.
In case you have a concern or query you can always consult a specialist & get answers to your questions!

Ask a free question

Get FREE multiple opinions from Doctors

posted anonymously

Book appointment with top doctors for Interstitial Lung Disease treatment

View fees, clinc timings and reviews

Treatment Enquiry

Get treatment cost, find best hospital/clinics and know other details